SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
As an EP, the device only expects to receive (and never transmit) configuration transactions, and expects those to be CFG0 and not CFG1.
Incoming Cfg accesses with the appropriate Target ID are automatically routed to the targeted EP function’s 4-KiB PCI configuration space, which contains both the PCI standard registers (header, descriptors, extende descriptors, and so forth) and the PL registers. The request read/write complete automatically, with no transaction appearing on the PCIe controller master port. Since Cfg accesses are non-posted, each incoming request shall generate a response.
An ATU inbound region is also capable of processing incoming Cfg transactions, and translating them into read/write accesses on the master port towards L3_MAIN. However, this method is not expected to be used, and automatic completion –described above– is expected to be used instead.